


shatterproof

by MiniNephthys



Category: Undertale (Video Game)
Genre: Dubious Consent, M/M, Plot What Plot/Porn Without Plot, Spoilers, Tentacles
Language: English
Status: Completed
Published: 2015-11-08
Updated: 2015-11-08
Packaged: 2018-04-30 14:05:49
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 1,627
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5166608
Author URL: https://archiveofourown.org/users/MiniNephthys/pseuds/MiniNephthys
Summary: <blockquote class="userstuff">
              <p>Sans has alone time, sort of, and someone else learns to ask nicely.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> If you would like to skip the heavily dubious consent part, the second chapter is entirely consensual, so you can go straight there!

Sans only gets the house to himself occasionally. Usually, it’s when Papyrus is having a sleepover with Undyne, like he is tonight. Papyrus spent a good amount of time fussing over him, making sure he had something to eat for dinner (even if it was spaghetti, Sans appreciates the thought) and telling him to go to bed at a reasonable hour and not immediately after he was out the door.

That’s often a valid concern. But tonight Sans has plans.

Not very exciting plans, mind. It’s just been a while since he’s been able to guarantee himself privacy in the relative comfort of his own home, and he’d like to relieve a little stress.

He settles on his bed, leaving the door unlocked and the lights off, and kicks off his slippers first. They thud against the wall, perilously close to being sucked into his trash tornado, and he reminds himself to stop doing that. The rest of his clothes are discarded a tiny bit more carefully.

Sans has an entire night, but he really wouldn’t know what to do with himself if he tried to stretch things out or spice things up. There’s only so much you can do with a bony hand on other, more sensitive bones. That’s fine with him: it’s not a priority or something he does that often.

Stroking his own bones firmly falls under the category of ‘nice’. His hand isn’t the softest, so he has to be careful and gentle, but rubbing underneath his ribcage is enough to start working him up, if ever so slowly. He shifts on the bed, hand trailing down to his pelvis and drawing out a tiny push of his hips towards the touch. His other hand reaches for his sternum, and finds before it gets there - something soft, and slightly wet.

That’s not any part of his body.

Panic strikes him at once. He tries to stand up, but that same substance grips his hips and wraps around his ribcage and holds him still. With the lights off, it’s hard to see anything clearly - he regrets making it pitch black just to set up a joke later - but he can just make out a darker mass, bubbling and shifting in front of him. There’s no way to tell what it is, but his first concern isn’t to identify it but to get it to let him go-

_Let you go...?_

A voice in the back of his head. He knows it isn’t his, but he doesn’t recognize the owner. His body seems to, though, stilling its struggles even though the fear hasn’t yet left Sans’ mind.

_You used to let me do this for you all the time, Sans._

Whatever is holding him slips inside his bones, sliding against the inside of his ribcage. It’s softer than Sans’ hand, and touching more of him at once. He grits his teeth to hold back a sound he knows he wouldn’t like.

_Well. It was not quite like this, exactly._

As it continues to rub against him, the mass inside him expands, filling him up. He chokes back another moan, trying desperately to focus on escape over the flood of sensation that’s washing over him.

_But this isn’t so bad, is it? Not the worst part of the situation... No, the worst part is that you’ve forgotten. Hm. What to do?_

A dark tendril slips into his mouth, almost to the point of gagging but not quite. At least it muffles the sounds he’s making. That’s something.

_See, not so bad at all. You could enjoy it if you only weren’t so frightened._

Why is this happening to him?

_Why...?_

The grip on his hipbones tightens for a moment.

_I miss you. I miss this, touching you, being close to you, but I miss you more. That must be why. With you, I can feel like a ‘me’ again._

For a moment, everything is still and quiet. Whatever, whoever is in Sans doesn’t move, and neither does he.

Some part of his mind, the rational part, wants to keep struggling. Some other part wants to try and give in and at least get some enjoyment out of what is clearly going to happen no matter what he does.

A third part, a quieter part, says that this isn’t someone he should have to struggle against in the first place.

The mass slips out of Sans’ mouth, brushing against the bones of his face like a gentle kiss. The tendrils holding his body still fade away, though part of it is still inside of him and rubbing against him every time he moves. He shivers.

_Sans._

The voice in his mind is softer now.

_Would you trust me?_

Sans’ voice, when he finds it, is hoarse. “...If you warned me before you tried to jump my bones, maybe.” For the moment he ignores that whoever this is was doing more than ‘trying’ to jump his bones, and is still technically in the middle of that.

_So sorry. Thought you might say no. That’s no excuse, is it?_

“Not really.”

The rest of the mass finally leaves his body, leaving him feeling strangely empty. In the darkness, he can no longer tell if anything at all is there, or was ever there.

_A warning, next time. Completely reasonable. Understood._

The voice fades away, leaving Sans unsatisfied in a number of ways. Mostly the way that involves wondering what just happened. Also the way that involves trying to finish getting off.

He doesn’t know if he’s afraid of the next time Papyrus has a sleepover, or looking forward to it.


	2. Chapter 2

Papyrus has another sleepover.

Sans is a bundle of nervous energy, enough that Papyrus notices before he leaves and asks if there’s anything he’s planning. Sans’ voice almost breaks when he says no.

This is something he doesn’t want to explain to Papyrus. He doesn’t even know where he’d begin.

When Papyrus is out of the house, Sans heads directly to his bedroom. This time, he keeps the lights on as he sits on his bed.

Nothing happens. A not unreasonable part of Sans suggests that he may have dreamed the last encounter up entirely. It was weird as hell and not something you could expect to happen in reality, or to happen twice.

He sighs, and flips the lights off. As soon as he does-

_Thank you. This body is... a little embarrassing, so I wouldn’t want you to look at it._

“Should’ve just said something,” he answers, and tries not to think about the ease at which he’s talking to a voice in his head that wants to have tentacle sex with him.

_Would it be easier for you to think of it as just sex? That only happens to involve tentacles?_

“It’s pretty much the same thing no matter how you look at it.” He parks himself back on the bed. A few tentacles tug off his slippers, setting them neatly aside. They hover around his jacket.

_May I?_

He gives a nod, though nobody would be able to actually see it in the darkness. The tendrils react anyway, carefully removing his jacket. They do the same to the rest of his clothes, and he thinks by the sounds that they’re even folding them.

A brush against his collarbone. Feather-light, as if questioning if it’s okay to touch. He appreciates it far more than last time’s sudden surprise. He sits back, hands planted firmly on the bed. Go for it.

A few more tendrils rub against his hipbones, not holding him still this time, just stroking gently. One curls around a rib and he gasps, not trying to hide his noises this time.

_I like that... I like that very much. Will you make more sounds for me, Sans?_

More tentacles, thin and delicate, slide between his ribs and begin to stroke, inside and outside at once. Sans’ fingers grip tightly onto his sheets as he moans, wordless.

More tentacles. These ones slide around other bones: his pelvis, his collarbone, anywhere they can provoke a reaction. Sans feels surrounded, but this time no panic rises up within him.

_I’m so glad... You make me so happy._

He doesn’t have the ability to answer that out loud. Not with the mass squirming and filling him more and more, in constant motion, sliding against almost every bone in his body. Instead of speech, all that leaves him are gasps and groans.

The onslaught of sensation continues. His hips are jerking and trembling, his body shakes, it’s all too much too soon-

He doesn’t last very long.

Whoever it is senses when he’s done and pulls out of and away from him. The last touch is a light brush on his cheek, something that would be tender if he knew who was giving it to him.

_Don’t concern yourself too much over that. It’s nothing you could remember, and if you did, it would be bad for you. I don’t want that._

Though it shouldn’t make much of a difference to him either way, Sans feels... something at those words. A sense of loss, maybe. Grief, but dulled so much it can hardly be distinguished any longer.

_Don’t be so sad, Sans. You have too much to be sad over already._

That tentacle brushes his mouth again, an almost kiss.

_I’ll come again, if I can, but it may not be possible in this timeline. Even so, I’m glad I spent the time here, with you._

The touch disappears, and the voice goes quiet.

Sans waits for a while, silent, then goes to bed feeling empty. Emptier than usual.

In the morning, he wakes up to find that his clothes are neatly folded by the side of his bed.


End file.
